Heart valve replacement has become common practice and saves lives.
In order to surgically implant a prosthetic heart valve into a patient, the patient may need to be placed on cardiopulmonary bypass (CPB) during a complicated, but common, open chest procedure. In some cases, however, placing a patient on CPB may pose a significant risk and it may be desirable to avoid doing so if possible. Without CPB, the time available for performing the heart valve implantation is limited and it would be desirable to be able to perform the implantation procedure faster. Even with CPB, it is desirable to reduce the length of time in which the patient is under CPB. If CPB can be completed within a reduced time, it is expected that the patient survival rate can significantly increase and the morbidity can significantly decrease.
Prosthetic heart valves such as collapsible or injectable heart valves can be delivered into a patient's heart using a catheter or trocar. Such a procedure may be done in a less invasive manner than surgical procedures such as open-chest or open-heart surgery, which may be required for delivering non-collapsible heart valves.
There are known techniques for loading the heart valves into a catheter or trocar for delivery of the heart valve into the patient's body. Example devices and procedures are described in U.S. Pat. No. 7,803,185 to Gabbay, entitled “Method of implantation of a heart valve prosthesis through a tubular catheter”; U.S. Pat. No. 7,311,730 to Gabbay, entitled “Support apparatus and heart valve prosthesis for sutureless implantation”; and U.S. Pat. No. 8,845,722 to Gabbay, entitled “Heart valve prosthesis and method of implantation thereof.”
It may be necessary to store collapsible prosthetic heart valves in a suitable solution in an uncompressed condition before surgery to maintain and preserve their structural integrity and desired property. It may also be necessary to cool certain prosthetic heart valves just before surgery so that the material becomes resilient and can be compressed and loaded into the delivery device. A known technique for loading a collapsible prosthesis into a delivery device is to push the prosthesis through a funnel attached to the delivery apparatus to gradually compress and reduce the radial size of the compressed prosthesis. An alternative technique is disclosed in U.S. Pat. No. 7,530,253 to Spenser et al., which disclosed a complicated prosthetic valve crimping device capable of reducing the diameter of an expandable prosthetic valve.
Simpler and faster devices and methods for implanting a heart valve are still desirable.